Cuttlefish are super cool and it's exciting that you are getting a tank set up for them! I have worked with Metasepia Pfefferi in the past (flamboyant cuttles) and I would strongly encourage you to start with a different species. This might be disappointing, but let me explain below.
There are a few reasons I caution any hobbyist aquarist against working with Metasepia. The first being that Metas are prohibitively expensive (typically upwards of $400 for an adult animal), don't travel well, and are extremely fussy to feed and care for. They are incredibly beautiful, but I can almost guarantee you that even in the ideal setup, adult Metasepia likely won't live longer than 1-2 months. Additionally, if you plan on co-housing your animals, you will have to be very careful to get the ratio of males/females correct, or the males will kill each other and the females in the tank.
I'm saying all this not to scare you or stop you from getting a cuttlefish, but to redirect your passion towards what I believe to be the most hobby-friendly cuttlefish, the Sepia Bandensis. They aren't nearly as colorful or frilly as Metasepia are, but they are much more hardy, usually only run about $120 for an adult individual, and I have actually succeeded in having one survive a shipment across the country. You will still have to be careful about sex ratios if you plan on housing more than one in a tank, but that can be covered at a later date.
Do you plan on purchasing full grown adults? Juveniles? Or buying eggs and raising them from babies? I may be able to make suggestions for a vendor depending on what exactly you are looking for.
I'm happy to give more advice if you need. Cuttlefish are incredibly delicate and fussy, but successfully keeping one at home can be extremely rewarding and a wonderful learning experience.